Minnesota Tornado History and Statistics
Tornadoes are among the most devastating and awesome local storms that occur in the world. The United States has the dubious distinction of having the greatest frequency and the most severe tornadoes. They have the power to lift railroad cars and sail them many yards through the air. The power of their winds can make deadly missles of loose objects, including broken glass. Even pieces of straw have been found imbedded in trees and boards after a tornado.
During the winter months (December through February) tornado activity is concentrated in the southeast U.S. and along the gulf coast. As spring (March/May) progresses tornado occurrence moves north and west across the central Mississippi and Ohio River Valleys. By summer (June/August) the potential threat of tornadoes has spread across the continental United States and Southern Canada. During autumn (September/November) tornadic activity gradually retreats to the south and southeast sections of the country.
This seasonal drift is principally caused by the increase of warm, gulf moisture into the central part of the country during spring and summer, decreasing during the fall and winter. The mixing which occurs when the moist gulf air clashes with contrasting colder, drier air from the north and northwest contributes to the triggering of tornadoes.
Minnesota lies along the north edge of the region of maximum tornado occurrence in the United States. Tornado Alley, as that part of the central U.S. has come to be known, reaches across parts of Texas, Oklahoma, Kansas, Missouri, East Nebraska, and West Iowa.
In Minnesota, tornadoes have occurred in every month from March through November. The earliest verified tornado in Minnesota occurred on March 18, 1968, north of Truman, and the latest in any year on November 16, 1931, east of Maple Plain. Historically and statistically, June is the month of greatest frequency with July not far behind. May has the third greatest frequency, followed closely by August. Nearly 3/4 of all tornadoes in Minnesota have occurred during the three months of May (16%), June (34%), and July (26%).
The most probable danger period in Minnesota, therefore, is late spring and early summer, between 2PM and 9PM. However, tornadoes can and do occur at any time of the day or night.
Despite a higher number of tornadoes reported in recent years, the number of fatalities and injuries due to tornadoes has been decreasing. This is thanks in part to better National Weather Service tools in detecting tornadoes, namely the NEXRAD dopper radar network installed in the mid 1990's. Also, the ability of alerting the public has improved as well with more National Weather Service radio transmitters and a close relationship with media outlets. An energetic spotter network has also been the key to alerting the public in Minnesota. There have only been 6 deaths due to tornadoes in Minnesota in the last 15 years (1992-2007) and there haven't been multiple deaths due to a single tornado since 1978. In fact, the increasing number of tornadoes reported may be a direct reult of improved communications networks, public awareness, warning systems and training.
Most of the deadly and damaging tornadoes occur in groups of outbreaks that often last from 6 to 12 hours. One of the worst such outbreak in Minnesota occurred on June 28, 1979, when 16 tornadoes slashed across the state, from northwest to southeast, in a six and one half hour period. Two additional tornadoes occurred in eastern North Dakota with this system. Many such outbreaks have occurred, including the April 30, 1967 cluster in south central and southeast Minnesota. The most tornadoes in one single day was 27 on June 16, 1992 that included an F5 tornado at Chandler.
Just by chance, some counties have not seen a tornado in years. The last
tornado reported in Ramsey County was in 1998. Benton County has gone the
longest without seeing a tornado. The last tornado spotted there was on June 16, 1992.
Some notable tornadoes from Minnesota history include:
The tornado which struck Rochester on August 21, 1883, (at 6:36PM) killed 37 and injured many others. This was a large factor in the subsequent development of the Mayo Clinic.
On April 14, 1886 (4PM) the deadliest tornado in Minnesota history razed parts of St.Cloud and Sauk Rapids, leaving 72 dead and 213 injured. 11 members of a wedding party were killed including the bride and groom.
August 21, was again a tornado day, in 1918 (9:20PM), this time at Tyler, killing 36 people.
Less than a year later, June 22, 1919, (4:45PM) 59 lives were lost when the second deadliest killer tornado in Minnesota history roared through Fergus Falls.
More than 220 people were injured and nine killed in the Champlin area on June 18, 1939 (2PM).
On August 17, 1946, about an hour apart, tornadoes slashed through the cities of Mankato and North Mankato (5:40PM) leaving 11 dead and 60 injured, and Wells (6:50PM) where some 200 persons were injured.
Part of a larger outbreak on May 10, 1953, three tornadoes it southeast Minnesota killing seven and injuring 19.
The Fargo, ND/Moorhead, MN tornado of June 20, 1957 (6:40PM) left 10 dead and more than 100 injured in its wake.
The most damaging series of tornadoes in Minnesota slashed across west and north sections of the Twin Cities Metro area (between 6PM and 9PM) on May 6, 1965. 14 persons were killed and 685 injured with damage in excess of 50 million dollars.
On this day eight tornadoes struck south central MN including three that were rated F4. 11 people were killed and 81 were injured. A four block wide swath was cut in the town of Waseca.
Tracy was in the path of a destructive tornado on June 13, 1968, (7:02PM) which killed 9 and injured 125 people.
The maxi-tornado which struck the Outing area on August 6, 1969, (4:02PM) left 12 dead and 70 injured.
A memorable tornado in Minnesota with one death
and 83 injuries, tore across the Twin Cities from Edina to
Roseville on June 14, 1981.
The greatest March tornado outbreak in Minnesota history was March 29, 1998.
Two people died in a family of 13 tornadoes that stuck St. Peter
and Comfrey especially hard.
A tornado struck Granite Falls on July 25, 2000 and caused one death and 15 injuries.
A more recent killer tornado in Minnesota was when an elderly man died at Lake Emily near
Kasota on August 24, 2006.
The last killer tornado (through 2007) in Minnesota was when a 10 year old girl died in Rogers on September 16, 2006.
| 1950 - 2007 | Totals | Annual Averages |
| Tornadoes | 1482 | 25.6 |
| Tornado Deaths | 94 | 1.62 |
| Tornado Injuries | 1862 | 32.1 |
| Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Total | |
| Total | 19 | 71 | 236 | 503 | 379 | 170 | 76 | 27 | 1 | 1482 |
| Average | 0.3 | 1.2 | 4.1 | 8.8 | 6.6 | 3.0 | 1.3 | 0.5 | 0.02 | 26 |
| Percent | >1 | 5 | 16 | 34 | 26 | 11 | 5 | 2 | 0 | 100 |
| One Year | 74 in 2001 |
| One Month | 38 in June 2001 |
| One Day | 27 June 16, 1992 |
| Location | Date | Time | Deaths | Injuries |
| Ft. Snelling (First tornado reported in Minnesota) | 4/19/1820 | 11 PM (est) | 0 | 0 |
| Rochester | 8/21/1883 | 6:36 PM | 37 | 200 |
| St.Cloud/Sauk Rapids (Most deaths from a single tornado in Minnesota) | 4/14/1886 | 4:00 PM | 72 | 213 | Lake Gervias (Ramsey County) Widely visible throughout St. Paul | 7/13/1890 | 5:30 PM | 6 | 30 |
| Minneapolis/St.Paul (Could have been straight-line winds or microburst.) | 8/21/1904 | 7:30 PM | 14 | unknown |
| Tyler | 8/21/1918 | 9:20 PM | 36 | 225 |
| Fergus Falls | 6/22/1919 | 4:45 PM | 57 | 200 |
| Champlin | 6/18/1939 | 2:00 PM | 9 | 222 |
| Mankato/North Mankato | 8/17/1946 | 5:40 PM | 11 | 100 |
| Wells | 8/17/1946 | 6:50 PM | 0 | 30 |
| South East Minnesota (Family of tornadoes) | 5/10/1953 | 4-5 PM | 7 | 19 |
| Fargo/Moorhead | 6/20/1957 | 6:40 PM | 10 | 103 |
| West-North Twin Cities (Family of tornadoes.) | 5/6/1965 | 6-9 PM | 14 | 683 |
| South Central Minnesota (Family of tornadoes.) | 4/30/1967 | 6-8 PM | 11 | 81 |
| Tracy | 6/13/1968 | 7:02 PM | 9 | 125 |
| Outing | 8/6/1969 | 4:02 PM | 12 | 70 |
| Gary | 7/5/1978 | 1:45 AM | 4 | 38 |
| Roseville-Har Mar | 6/14/1981 | 3:49-4:15 PM | 1 | 83 |
| St. Anthony-Apache Plaza | 4/26/1984 | 8:33-8:41 PM | 1 | 52 |
| Brooklyn Park. Viewed live on TV. See the KARE-11 Newscast part 1 part 2 | 7/18/1986 | 3:47-4:27PM (est) | 0 | 0 |
| Chandler (Last F5 tornado in Minnesota.) | 6/16/1992 | 4:00 PM | 1 | 35 |
| Littlefork (Last multiple deaths due to single tornado.) | 8/9/1993 | 1:35 AM | 2 | 0 |
| Comfrey/ St. Peter | 3/29/1998 | 4:30 PM | 1 | 16 |
| Granite Falls | 7/25/2000 | 4:57 PM | 1 | 15 |
| Kasota | 8/24/2006 | 5:30-6:25PM | 1 | 37 |
| Rogers (Last tornado to cause a fatality in Minnesota) | 9/16/2006 | 9:58 PM | 1 | 0 |
Links to tornado-related sites
- Minnesota Tornadoes by County 1950-2005
- Annual Severe Weather Report Summary
- Minnesota Tornadoes 2007 from the National Weather Service
- Minnesota Tornadoes 2006 from the National Weather Service
- Minnesota Tornadoes 2005 from the National Weather Service
- Minnesota Tornadoes 2004 from the National Weather Service
- Minnesota Tornadoes 2003 from the National Weather Service
- Minnesota Tornadoes 2002 from the National Weather Service
- Minnesota Tornadoes 2001 from the National Weather Service
- Minnesota Tornadoes 2000 from the National Weather Service
- Minnesota Tornadoes 1999 from the National Weather Service
- Minnesota Tornado Statistics (1950-1995) from the Tornado Project
- Central and Southern Minnesota County Tornado Statistics from the Chanhassen National Weather Service
- Worst Minnesota Minnesota Tornadoes (1879-1995) from the Tornado Project
- The Tornado Project
- Storm Prediction Center
- National Severe Storms Laboratory
- Tornado photographs from the Minnesota Historical Society
